The approaches described in this section could be pursued, but are not necessarily approaches that have been previously conceived or pursued. Therefore, unless otherwise indicated herein, the approaches described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
It is desirable to prioritize and segregate or isolate network traffic in routers and routing systems. Certain types of control traffic, such as BGP, however, do not lend themselves to prioritization and segregation or isolation using conventional methods. (BGP is a protocol used by routers and other route entities to exchange routing information about each router's respective networks or routing routes.) This is due to the nature of the traffic, the quantities of information sent and the timing of the sending of the information. In the case of BGP, for example, large amounts of data may be transmitted in reasonably short periods of time, giving BGP a “bursty” nature. This is especially true during periods of so named “convergence.” As used herein, the term “convergence” refers to that time in which chum or change occurs in a network, which requires updating of routing information in the routing entities of the network.
In the case of BGP, traffic can be loosely classified into two categories: 1) BGP update traffic; and 2) BGP control traffic. The first category includes the bulk of BGP traffic and comprises updates to routing information for the routing entities in a network. The latter classification of traffic includes messages, such as BGP keepalives, BGP route-refreshes, BGP opens, BGP notifications, BGP soft-notification messages and the like. Typically, the volume of BGP control traffic is relatively small compared to the volume of BGP update traffic. Accordingly, it would seem that BGP could benefit from some form of prioritization and segregation.
However, because of BGP's bursty nature, and because BGP is typically implemented using TCP, conventional prioritization and segregation schemes often fail. Prioritization and/or segregation of a TCP stream is not easily accomplished and conventional approaches do not provide full prioritization. For example, in many conventional approaches, if any other traffic is being transmitted in the same TCP session, the receiving, or remote, side will still wait for previously transmitted message segments to be received before the remote side passes any prioritized message segments to an application residing on the remote side.
Based on the foregoing, there is a clear need for a mechanism for prioritizing and sending control traffic, such as BGP traffic, between routers and other routing entities.